Global Rivers Contaminated by Human Antibiotic Use, Study Warns of Rising Drug Resistance Risk

Hello and welcome to our May 11th edition. The STEAM Digest is a curated newsletter that brings you the latest in science, technology, engineering, arts, and mathematics.

In today’s edition:

• Science - Chemists Develop Low-Cost, Precise Method for Protein Labeling Using Bacteria, and more.

• Materials - New Micropipette Enables Precise Ion Delivery to Individual Brain Cell.

• Biotechnology - New Cooling System Could Boost Quality, Profit, and Sustainability for Small Fishing Boats.

• Engineering & Technology - Boiling Water Powers Next-Gen Soft Robots with High Force and Precision, and more.

• Robotics, AI, Hardware, Software, Gadgets - MIT’s Robotic Arm Serves Up Precision in High-Speed Ping Pong Play, and more.

• Health & Medicine - Time-Restricted Eating Helps Sustain Long-Term Weight Loss, Regardless of Meal Timing, and more.

• Pediatrics - Phthalate Exposure Linked to Altered Genital Development in Young Children, and more.

• Neuroscience - UCLA Researchers Map Gene Networks Driving Human Brain Development.

• Environment & Earth Sciences - Global Rivers Contaminated by Human Antibiotic Use, Study Warns of Rising Drug Resistance Risk.

• Nature & Ecology - Researchers Warn of Bird Flu Threat in Cats as Potential Bridge to Human Transmission, and more.

• Other Sciences & The Arts - Revealing the Craftsmanship of Dahomey: Neutron Analysis Sheds Light on 19th Century West African Swords, and more.

Until Tomorrow,

~The STEAM Digest

If you would like to share The STEAM Digest newsletter with others, please use the following link: https://thesteamdigest.beehiiv.com/subscribe

SCIENCE

Chemists Develop Low-Cost, Precise Method for Protein Labeling Using Bacteria:
Chemists have developed a fast, precise, and cost-effective method for labeling proteins, making it easier to study protein behavior within cells. The study introduces a technique using genetic code expansion to engineer bacteria to produce proteins containing special amino acids that can be fluorescently tagged. Unlike current approaches, which rely on expensive chemicals and complex procedures, this method uses inexpensive, accessible compounds and avoids toxic catalysts, making it more environmentally sustainable. The labeled proteins can be observed under a microscope, aiding research in drug development, diagnostics, and cellular biology.

Hospital Superbug Found to "Eat" Medical Plastic, Raising New Infection Control Concerns: Researchers have discovered that Pseudomonas aeruginosa—a dangerous hospital-acquired superbug—can degrade and digest polycaprolactone (PCL), a plastic commonly used in sutures, implants, stents, and wound dressings. The study shows that the bacteria use the plastic as a carbon source to survive, helping them form stronger biofilms that resist antibiotics and persist in hospital environments. The team isolated an enzyme, Pap1, which degraded 78% of a plastic sample in just seven days. Signs of similar enzymes were also found in other pathogens, suggesting that widely used medical plastics—like polyethylene terephthalate and polyurethane—could also be at risk. The findings raise urgent questions about medical device safety, hospital infection control, and the potential need for plastic materials resistant to microbial digestion.

MATERIALS

New Micropipette Enables Precise Ion Delivery to Individual Brain Cells: Researchers have developed an iontronic micropipette—a novel tool that allows the precise delivery of ions to individual neurons without disturbing the brain’s delicate extracellular environment. The study demonstrates how this 2-micrometer-wide pipette, fitted with an ion-exchange membrane, can chemically stimulate both neurons and glial cells, especially astrocytes, offering new insights into brain cell communication. Unlike previous methods that introduced fluids and disrupted pressure or balance, this approach modulates ion concentration alone, enabling highly localized and controlled experiments. Tested on mouse hippocampal tissue, the tool revealed unexpectedly dynamic astrocyte responses, preceding neuronal activation. The team envisions future applications in neurological research and treatment, including precision drug delivery for conditions like epilepsy.

BIOTECHNOLOGY

New Cooling System Could Boost Quality, Profit, and Sustainability for Small Fishing Boats: A new plug-and-play refrigerated seawater (RSW) cooling system developed for small fishing vessels is being tested in Norway, offering the potential to extend shelf life, reduce food waste, and improve animal welfare. While 80% of Norway’s fishing boats are small, only 5% of their catch is refrigerated, leading to quality loss and waste. The new system, using natural CO₂ refrigerant and offering 8 kW of cooling power, helps preserve temperature-sensitive seafood like langoustines, which often suffer high mortality from temperature shocks. The compact, durable system enables longer trips, lower fuel use, and higher product quality. Researchers estimate that global seafood waste could be cut from 30% with wider use of such technology, and the system may soon become a game-changer for sustainable small-scale fisheries.

ENGINEERING & TECHNOLOGY

Boiling Water Powers Next-Gen Soft Robots with High Force and Precision:
Researchers have developed a new class of soft actuators powered by the liquid-to-gas phase transition of water, offering a simple, low-voltage, and scalable alternative to traditional pneumatic systems. The study showcases how embedded heating elements can convert water to steam, generating internal pressure to drive soft robotic motion. The modular actuators—capable of delivering over 50 N of force and pressurization rates up to 100 kPa/s—demonstrated success in powering a biomimetic hand, a soft gripper, and a quadruped robot. This innovation promises safer, more sustainable, and cost-effective soft robotics suitable for real-world environments.

Breakthrough in Warm Metalworking Enables Flexible Processing of Brittle Inorganic Semiconductors: A team of researchers has demonstrated that traditionally brittle inorganic semiconductors—such as Cu₂Se, Ag₂Se, and Bi₉₀Sb₁₀—can undergo plastic warm metalworking at temperatures below 200°C, enabling new possibilities for flexible and cost-effective electronic manufacturing. The study shows these materials can be rolled, compressed, or extruded into free-standing, high-performance films with thicknesses down to micrometers and carrier mobilities up to 5,000 cm² V⁻¹ s⁻¹—far exceeding silicon and many organic alternatives. The researchers developed a model explaining the temperature-induced ductility and successfully applied the technique to build thermoelectric devices with nearly double the power output of conventional devices. This innovation paves the way for scalable, substrate-free fabrication of next-generation electronics and energy systems.

Next-Gen Supercapacitor Combines Carbon Nanotubes and Polyaniline for Fast, Durable Energy Storage: A research team has developed a high-performance supercapacitor that overcomes the energy limitations of conventional designs by combining single-walled carbon nanotubes (CNTs) with the conductive polymer polyaniline (PANI). This nanostructured composite fiber enables rapid electron and ion transport, resulting in a supercapacitor with enhanced energy density, fast charging, and stability over 100,000 cycles—even in high-voltage conditions. The CNT-PANI fibers are also flexible, low-cost, and suitable for mass production, making them ideal for applications in electric vehicles, drones, robots, and wearable electronics. The innovation lays the groundwork for scalable, sustainable energy storage critical to a carbon-neutral future.

ROBOTICS, AI, HARDWARE, SOFTWARE, GADGETS

MIT’s Robotic Arm Serves Up Precision in High-Speed Ping Pong Play: MIT engineers have developed a lightweight, high-speed robotic arm capable of returning ping pong balls with precision, achieving an 88% hit rate across various swing styles like loop, chop, and drive. Powered by real-time motion capture and predictive control algorithms, the robot mimics competitive play by estimating a ball’s speed and spin and responding within milliseconds. Designed using modified components from the MIT Humanoid project, the arm delivers paddle strike speeds up to 19 meters per second, nearing human performance levels. Beyond table tennis, the technology could be adapted for humanoid robots in dynamic environments, such as search-and-rescue operations, where fast object interception is critical. The team aims to enhance the robot’s mobility and accuracy, with future applications in robotic training systems and more generalized, agile robotics.

Robots Learn to "Feel" Objects by Shaking Them—No Cameras Needed: Researchers have developed a novel technique that allows robots to infer an object's physical properties—like weight or softness—by picking it up and gently shaking it, using only internal sensors. Unlike traditional methods that rely on external cameras or tactile sensors, this low-cost approach uses proprioception and joint encoder data to analyze how an object affects the robot’s motion. Leveraging differentiable simulation, the system can estimate characteristics in seconds with high accuracy. This method could enhance robotic performance in low-visibility environments or disaster scenarios and pave the way for more adaptive and physically aware robots.

AI Tool "FaceAge" Estimates Biological Age from a Photo to Guide Medical Decisions: Researchers have developed FaceAge, a deep learning algorithm that estimates a person's biological age from a headshot, offering potential improvements in medical decision-making. FaceAge was trained on nearly 59,000 photos of healthy adults and tested on over 6,000 cancer patients, consistently predicting poorer outcomes for those with higher biological age scores—even beyond traditional age-based metrics. Unlike human perception, the model emphasizes subtle facial cues over visible aging signs like gray hair. While promising for tailoring treatments such as cancer care or surgeries, the tool raises ethical concerns around privacy, bias, and misuse by insurers or employers. Further validation is underway, including a planned public portal for broader research use.

HEALTH & MEDICINE

Time-Restricted Eating Helps Sustain Long-Term Weight Loss, Regardless of Meal Timing: A 12-month follow-up of a randomized controlled trial presented at the European Congress on Obesity reveals that time-restricted eating (TRE)—limiting food intake to an 8-hour window—can lead to sustained weight loss in adults with overweight or obesity, regardless of whether the eating period occurs earlier or later in the day. Conducted in Spain, the study found that participants in all TRE groups lost significantly more weight and reduced waist and hip circumferences after 12 weeks compared to those who ate over 12 hours or more. After one year, early and late TRE groups maintained significantly greater weight loss than the habitual eating group, with high adherence and no serious adverse events reported. The findings suggest that a simple 3-month TRE intervention may offer a practical, long-term alternative to traditional calorie-counting diets.

Infertility Linked to Increased Risk of Heart Disease and Stroke in Women: Women with a history of infertility face a significantly higher risk of developing cardiovascular conditions later in life, according to a large meta-analysis presented at the joint ESPE-ESE congress. Greek researchers reviewed data from 21 studies involving over 3.5 million women and found that infertility was associated with a 14% increased risk of heart and vascular disease, a 17% increased risk of heart disease, and a 16% increased risk of stroke. Risks were even higher for women under 40 and those who had undergone assisted reproductive technologies (ART). The findings suggest infertility may serve as an early warning sign for future heart health problems, underscoring the need for long-term cardiovascular monitoring and preventive care in affected women.

Low Blood Phosphate Linked to Reduced Sperm Motility in Infertile Men: Researchers have discovered that infertile men are significantly more likely to have low levels of phosphate in their blood, and that these lower levels are associated with reduced sperm motility. The study analyzed blood and semen samples from 1,242 infertile men and found that 36% had clinically low phosphate, compared to 2–4% in the general population. While low phosphate was not linked to sperm count, it correlated with poorer sperm movement and higher estradiol levels. A second study by the same team showed that higher phosphate concentrations in semen are linked to better sperm quality and testosterone levels, suggesting phosphate plays a crucial role in testicular and sperm function. The researchers now plan controlled trials to explore phosphate supplementation as a potential fertility treatment.

PEDIATRICS

Phthalate Exposure Linked to Altered Genital Development in Young Children:
New research shows that high levels of phthalates—endocrine-disrupting chemicals found in common consumer products—are associated with shorter anogenital distance (AGD) in children, a marker linked to reproductive health. The study followed 188 children and their mothers from birth to age 3. Results revealed that maternal phthalate exposure was linked to shorter AGD in boys, while girls’ AGD was impacted by their own direct exposure. These findings raise concerns about widespread phthalate exposure and its potential long-term effects on sexual development and fertility, prompting calls for stronger public health measures and continued monitoring as children approach puberty.

Early Antibiotic Use in Girls Linked to Higher Risk of Early Puberty: A large South Korean study has found that girls given antibiotics within their first year of life—especially in the first three months—have a significantly increased risk of early puberty, or central precocious puberty (CPP). The research analyzed health records of over 322,000 children and found that antibiotic use before 3 months of age raised the risk by 33%, with even greater risk when exposure occurred within the first 14 days of life. Additionally, exposure to five or more classes of antibiotics increased the risk by 22%. No similar association was found in boys. Researchers suggest that early antibiotic exposure may disrupt gut microbiome or hormonal pathways, influencing pubertal timing. The findings underscore the need for cautious antibiotic use in infancy to safeguard long-term health outcomes.

Early-Life Growth Strongly Influences Adult Height but Not Puberty Timing, Study Finds: A Swedish study reveals that growth patterns in the first two years of life significantly shape pubertal growth and adult height, but have little effect on the timing of puberty. Analyzing data from 4,700 individuals using the QEPS growth model, researchers found early-life growth accounted for 38% of pubertal growth variation and 67% of adult height variation, while pubertal growth contributed only 9% to adult height. Pubertal timing appeared to be more influenced by genetics and environmental factors. The findings reinforce the importance of monitoring early childhood growth as a predictor of long-term health and development.

NEUROSCIENCE

UCLA Researchers Map Gene Networks Driving Human Brain Development: Scientists have created a comprehensive "meta-atlas" of gene expression in the developing human brain by integrating decades of single-cell RNA sequencing data. The study identified key gene co-expression modules that guide how different brain cell types, especially neurons in the cerebral cortex, emerge and specialize. The researchers validated these gene networks using human brain tissue and 3D brain organoids, uncovering critical roles for genes linked to neurodevelopmental disorders. Their findings not only shed light on normal brain development but also offer a framework for understanding and potentially treating conditions like autism and intellectual disabilities.

ENVIRONMENT & EARTH SCIENCES

Global Rivers Contaminated by Human Antibiotic Use, Study Warns of Rising Drug Resistance Risk: A McGill University-led study has revealed that approximately 8,500 tons of antibiotics—around one-third of annual human consumption—are polluting river systems worldwide each year, even after passing through wastewater treatment. The study is the first to globally quantify river contamination from human antibiotic use. Using a model validated by data from nearly 900 sites, researchers found that amoxicillin is most frequently present at ecologically harmful levels, especially in regions like Southeast Asia with high use and inadequate wastewater infrastructure. The study underscores the risks of chronic low-level antibiotic exposure on aquatic ecosystems and the development of antibiotic resistance, highlighting the need for monitoring and mitigation—even before accounting for additional pollution from livestock and pharmaceutical industries.

NATURE & ECOLOGY

Researchers Warn of Bird Flu Threat in Cats as Potential Bridge to Human Transmission: A comprehensive global review led by researchers warns that H5N1 bird flu is rapidly evolving and spreading in cats, potentially increasing the risk of human transmission. The study documents 607 cat infections across 18 countries, with a 90% fatality rate among domestic cats and tigers. Cats contract the virus by eating infected birds, contaminated feed, or through contact with other infected animals, including cows and other cats. The researchers call for urgent surveillance of cat populations, especially in animal shelters and farms, as the virus may be mistaken for rabies and often goes undetected. With summer migration of birds underway and H5N1 already confirmed in 66 U.S. human cases, the team warns that cat-to-human transmission could escalate, underscoring the need for preventive action to protect both public health and pet welfare.

Erratic Light Exposure Disrupts Sex-Specific Brain Patterns in Birds, Raising Broader Health Concerns: A recent study reveals that irregular light exposure erases key molecular differences between male and female birds, particularly in the brain’s pineal gland, which regulates circadian rhythms via melatonin. Conducted by an international team of researchers, the study exposed chickens to unpredictable light during early life and found that chronic light stress disrupted sex-specific epigenetic patterns, especially in females. Despite epigenetic changes, gene activity retained some sex-specific traits, suggesting a compensatory biological response. The findings not only raise animal welfare concerns but also have implications for humans, as many people experience erratic lighting from shift work or screen exposure—potentially impacting their own circadian biology in subtle yet significant ways.

Chimpanzees Drum with Rhythm, Offering Clues to the Origins of Human Musicality: A new study reveals that chimpanzees drum rhythmically, with clear, nonrandom patterns that differ between subspecies—offering evidence that the roots of human musical rhythm may lie in our common ancestry. Researchers analyzed 371 drumming bouts from 11 chimpanzee communities and found that western chimpanzees preferred evenly spaced, faster beats, while eastern chimpanzees often used alternating intervals. The study suggests that chimp drumming serves communicative functions across distances and that rhythmic ability—once thought to be uniquely human—may have evolved millions of years ago in a shared ancestor.

OTHER SCIENCES & THE ARTS

Revealing the Craftsmanship of Dahomey: Neutron Analysis Sheds Light on 19th Century West African Swords: An interdisciplinary study used non-invasive neutron techniques to analyze six 19th-century swords from the West African kingdom of Dahomey (now Benin). Findings revealed that the swords—likely used by Dahomey's famed female warriors—were forged locally, countering earlier assumptions of European import. Advanced imaging methods, including neutron tomography and diffraction, uncovered differences in forging techniques, internal porosity, stress distribution, and composition, identifying three distinct manufacturing groups. While the exact origin of the iron remains uncertain, evidence suggests local iron was favored for ritual significance. The research highlights African metallurgical sophistication and ANSTO’s role in heritage science.

Behavior-Based AI Method Identifies Online Trolls Without Analyzing Content:
Researchers have developed a novel method to detect harmful online behavior by analyzing user interactions rather than content. The study uses inverse reinforcement learning to identify behavioral patterns in Reddit users, revealing personas like “disagreers” who habitually seek conflict. This approach overcomes limitations of content and network analysis, especially on platforms like Reddit where user connections are implicit. The findings suggest that behavior-driven moderation could be a powerful tool to curb misinformation and toxic engagement across diverse online communities.